Adjustable alligator-wrench.



L. MARSH.

ADJUSTABLE ALLIGATOR WRENCH.

APPLICATION FILED JAN.25. i911.

1,226,851, Patented May15,1917.

L UP a JUN!!! LUTHER MARSH, 0F PHILADELPHIA, PENNSYLVANIA.

ADJUSTABLE ALLIGATOR-WRENCH.

Specification of Letters Patent.

Patented May 15, 1917.

Application filed January 25, 1917. Serial No. 144,398.

To all whom it may concern:

Be it known that I, LUTHER Mansir, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a certain new and useful Adjustable Alligator- Wrench, of which the following is a specification.

The present invention relates to wrenches and more particularly to the type used in connection with pipes, rods, round bar stool; and the like and has for an object to provide a wrench wherein adjustment of the jaw opening n'ia-y behad to increase or decrease the range of operation so that a single wrench of given size can be used with a considerable number of pipes of varying diameter.

A further object of the invention is to provide a wrench of the general form and configuration of an alligator Wrench but having a movable jaw while its associated parts are so designed as to permit the drop forging process to be applied to their manufacture.

A further object is to provide a wrench having a movable jaw and a fixed jaw so con nected and related with respect to the fulcrum of the wrench that the most effective leverage is obtained While at the same time the danger of breaking the working is reduced to a minimum.

For the purpose of illustrating my invention, I have shown in the accompanying drawings one form thereof which is at present preferred by me, since the same has been found in practice to give satisfactory and reliable results, although it is to be understood that the various instrumentalities of which my invention consists can be variously arranged and organized and that my in vention is not limited to the precise arrangement and organization of the instrumentalities as herein shown and described.

Referring to the drawings:

Figure 1 represents'a front elevation of a wrench embodying my invention.

Fig. 2 represents a plan of one of the wrench members. I

Fig. 3 represents a side elevation of the part shown in Fig. 2.

Fig. 4 represents a side elevation. of the movable jaw of the wrench.

Fig. 5 represents a plan of the same.

Fig. 6 represents the bearing pin.

Fig. 7 represents the leader nut.

l designates the handle of the Wrench formed in the present instance as a substantially elongated part having at one end a fixed jaw 2 and an intermediate body portion 3 the purpose of which will presently appear. The jaw 2 is provided with an inclined plane bearing face l juxtaposed with respect to the toothed surface 5 of the jaw 6 which is pivotally connected to the body 3 by means of the pivot pin 7 which passes through the transverse openings 8 of the two jaw members. In connection with the body 3, it will be noted. that there is a recess or seat 9 formed therein to receive an arm 10 which is integral with the jaw 6 and extends rearwardly thereof and terminates in a worm rack 11 whichforms a means to operate the jaw 6 at will as required. In connection with the recess of the body 3 it will be obvious that this construction provides shoulders 12 respectively at each side of the body which serve as abutments or stops to limit the throw of the arm 10 and consequently the jaw opening.

13 designates a leader nut mounted for free rotary movement upon the bearing pin 14- and having worm teeth formed thereon to mesh with the teeth of the rack 11 so that rotation of the said nut causes the arm 10 to move in the desired manner from one side to the other according to requirements. The pin 14 is threaded at one end as shown at 15 for engagement with the threaded opening 16 of the handle body and passes across the opening 17 provided for the nut 13 into the socket 18 at the opposite side of the handle as will be understood. Ubviously this is only one means of securing the nut in its operating position and any well known means may be employed to carry out the same end without departing from the invention. I

Referring to Fig. 1, the wrench is shown in its normal position with the two jaws spaced apart and at the limit of movement in the closed direction of movement and in this position it will be noted that the axial line AB of the wrench handle practically bisects the angle formed by the jaws so that when the wrench is applied to a pipe or cylindrical stock the jaws engage and hold with a maximum efliciency.

The action of the wrench is substantially that of the alligator type in that it is adapted, when once adjusted for a particular size, to be placed in position with thejaws straddling, or partly so at least, the pipe to be gripped. In this position pressure upon the handle 1 in the desired direction causes the wrench to turn upon the pipe or other article and the teeth 5 to bite into the same to a suflicient extent to transmit the same turning movement to the article. The bite of the jaw teeth may be more or less regulated by turning the leader nut as desired, though ordinarily such adjustment is seldom necessary owing to the fact that when the jaws are once set for several sizes, the leverage produced by the proportioned length of the arm 10 is entirely effectual for the purpose required. Furthermore this leverage causes the teeth to bite promptly without appreciable slipping over the surface of the pipe and thereby marring of the pipe surface is materially reduced.

By reference to Fig. 1, it will be noted in this position, with the jaws open the mini mum, that the arm 10 is in contact with a shoulder 12 of the handle body 3 so that the pressure, under turning movement, is direct from the body to the arm 10, thus being more uniformly distributed and not subjecting any one part to an excess strain.

A further advantageous feature resides in constructing the pivoted jaw controlling means so that its adjusting movement toward the fixedjaw islimited to confine the toothed part of the jaw to the opposite side of the longitudinal axis of the handle from the fixed jaw as thereby the most effective leverage is obtained without placing either jaw under excess shearing strain. Also it will be noted that the arm 10 has a length which is substantially equal to the effective lever arm of the pivoted jaw, this latter length being determined by the distance between the pivot pin 7 or fulcrum and the normal point of contact of the jaw 6 with a pipe. It will be understood that in the normal operation of .an alligator wrench the pipe or like article is engaged intermediate the length of the jaw and seldom by the outermost tooth or teeth.

In connection with the worm rack 11 it will be noted that the width of the rack is the full thickness of the arm so that a relatively large bearing area is provided for engaging the leader nut. Preferably the length of theare of the rack is equal to or greater than one quarter the circum- Oopies of this patent may be obtained for five cents each, by addressing the ference of the leader nut in order to provide the aforesaid bearing.

It will also be apparent that the handle and the jaw 6 with its arm 10 are designed to be drop forged and an excess of metal is thus obtained at the points subject to strain.

It will now be apparent that I have devised a novel and useful construction which embodies the features of advantage enumerated as desirable in the statement of the invention and the above description and while I have in the present instance shown and described the preferred embodiment thereof which has been found in practice to give satisfactory and reliable results, it is to be understood that the same is susceptible of modification in various particulars without departing from the spirit or scope of the invention as expressedin the claims or sacrificing any of its advantages.

What I claim is:

1. In a device of the character stated, a handle formed with and encircling a transverse slot, an opening formed as a continuation of said slot, a jaw formed integral with said handle, a separate aw piv oted to said handle and having a rearwardly extending lever arm provided with rack teeth, the rack. portion of said arm extending within said slot and adapted to abut either end of said slot to form a stop to limit the movement of said pivoted jaw and a worm leader nut mounted in said opening and meshing with said rack, whereby said pivoted jaw may be adjusted with respect to said fixed jaw.

In a device of the character stated, a handle formed with and encircling an opening, a jaw formed integral with said handle, a toothed jaw pivoted to said handle and having a lever arm provided with rack teeth, a portion of said lever arm projecting into said opening, a worm leader nut mounted in said opening and meshing with said rack teeth and means integral with said. handle and located respectivelyat opposite sides of said lever arm and in the path of movement thereof to limit the movement of said pivoted jaw.

In testimony whereof, I have hereunto signed my name.

LUTHER MAR-SH.

Witnesses EMMA MARsH, JosnrH'I-I. CoULrnR, Jr.

Commissioner of Patents,

Washington, D. G. 

